Britain has sold almost £50m-worth of arms to Turkey since the crackdown on opposition groups by the government of Recep Tayyip Erdoğan after last year’s failed coup attempt.

Newly published export statistics confirm that Turkey is now a major buyer of UK-made weapons.

Between 1 July and 30 September, the UK sold Turkey £26m-worth of ML13 licences, which relate to exports of armoured plate, body armour and helmets. In addition, Britain sold Turkey £8.5m-worth of ML10 licences, for aircraft, helicopters and drones, and almost £4m-worth of ML4 licences, for missiles, bombs and “counter-measures”.

Since 2015 the UK has sold Turkey £330m-worth of arms. The country is on the Department for International Trade’s list of “priority markets” for arms exports. But the sales come amid mounting concerns about the abuse of human rights. Last week Turkish MPs held a second and final round of voting on constitutional changes to give President Erdoğan sweeping new powers. Under the plans, he will be able to choose ministers and judges and the post of prime minister will be axed. Critics have seen the move as a power grab.

“The political situation in Turkey is unstable, and the crackdown has meant that the repression is getting even worse,” said Andrew Smith, of Campaign Against Arms Trade. “This should be a time for caution and the promotion of human rights, not arms sales. The government is always telling us how rigorous its arms export criteria supposedly are, yet it continues to arm and support repressive governments across the world. The aftermath of the coup attempt has seen an erosion of democracy in Turkey, and Whitehall should not be legitimising it. The rights of Turkish people are more important than arms company profits.”

An EU intelligence report claimed individual military officers, who did not rank above lieutenant or captain, might have felt “under pressure” to join the coup attempt in July because they knew that Erdoğan had planned to go after them for supporting the US-based cleric Fethullah Gülen in August anyway.

However, the government believes that arms exports can be a key growth driver for the UK economy. Ministers have been dispatched to a number of Gulf and Middle East states in recent months to promote British weapons. Last year the foreign secretary, Boris Johnson, talked of his desire to agree a “jumbo” trade deal with Turkey. But the UK’s position may put it at odds with the EU. A leaked confidential EU report last week suggested that Erdoğan had anticipated the coup and had sought to exploit it so that he could launch a campaign against his opponents.

The EU report said that the MIT, Turkey’s intelligence service, had begun compiling lists of “troublesome individuals” years ago. It said the lists also contained the names of “civil activists” who took part in anti-Erdoğan protests in Taksim Gezi Park, Istanbul, in 2013. “The huge wave of arrests in the days following the coup attempt was already previously prepared. The coup was just a catalyst for the crackdown prepared in advance,” the intelligence report, obtained by the Times, said.

A government spokesperson said: “The UK takes its arms export responsibilities very seriously and operates one of the most robust arms export control regimes in the world. We rigorously examine every application on a case by case basis against the consolidated EU and national arms export licensing criteria. Our export licensing system allows us to respond quickly to changing facts on the ground. We have suspended or revoked licences when the level of risk changes and we constantly review local situations.”